Chapter 2: Microorganisms: Friend and Foe

Q&A -Ask Doubts and Get Answers

Q
Microorganisms: Friend and Foe

Question:

Tick the correct answer.

(a) Yeast is used in the production of:

(i) sugar (ii) alcohol (iii) hydrochloric acid (iv) oxygen

(b) The following is an antibiotic:

(i) Sodium bicarbonate (ii) Streptomycin (iii) Alcohol (iv) Yeast

(c) Carrier of malaria-causing protozoan is:

(i) female Anopheles mosquito (ii) cockroach (iii) housefly (iv) butterfly

(d) The most common carrier of communicable diseases is:

(i) ant (ii) housefly (iii) dragonfly (iv) spider

(e) The bread or idli dough rises because of:

(i) heat (ii) grinding (iii) growth of yeast cells (iv) kneading

(f) The process of conversion of sugar into alcohol is called:

(i) nitrogen fixation (ii) moulding (iii) fermentation (iv) infection

Answer:

(a) Yeast (fungi) is a microorganism that is used in the preparation of bread and cake. It reproduces rapidly and produces CO2 during respiration. It is also used for the commercial production of alcohol and wine.

Thus, the correct answer is (ii) alcohol.

(b) Antibiotic is a medicine that kills or stops the growth of disease-causing microorganisms. Streptomycin is the type of antibiotic that is manufactured by specific microorganism.

Thus, the correct answer is (ii) Streptomycin.

(c) Malaria is caused by a protozoan called Plasmodium. The female Anopheles mosquito carries the parasite of malaria.

Thus, the correct answer is (i) female Anopheles mosquito.

(d) Disease causing microbes are carried by some animals and insects, they are called carriers. Houseflies and mosquitoes are carriers of some diseases. 

Thus, the correct answer is (ii) housefly.

(e) Yeast (fungi) is a microorganism that is used in the preparation of bread and cake. It reproduces rapidly and produces CO2 during respiration. When yeast is added to the dough after a few hours the dough rises because the yeast cell reproduces and releases carbon CO2 gas which fills the dough and increases its volume. 

Thus, the correct answer is (iii) growth of yeast cells.

(f) The process of the conversion of sugar into alcohol by yeast is called fermentation.

Thus, the correct answer is (iii) fermentation.


Related Questions for Study

What our students and parents say about us!

Choose EduSakshamยฎ
Embrace Better Learning

edusaksham-mobile-app